One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,4)(6,9)(10,11)(13,14,16,18)(15,17,19,20)(21,22)(23,26)(24,27)(25,28)(29,36)(30,34)(31,33)(32,35)(5,6,8,9)(7,11,12,10)(13,15)(14,17)(16,19)(18,20)(21,23)(22,26)(24,30)(25,29)(27,34)(28,36)(31,32)(33,35)(7,12)(10,11)(14,18)(17,20)(22,27)(23,29)(25,32)(26,33)(30,31)(34,36) involution — undirected(2,4)(5,7,8,12)(6,10,9,11)(15,19)(17,20)(23,30)(26,34)(29,31)(33,36)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.